1. Field of the Invention
The present invention relates to a digital multifunction peripheral, which is a computer peripheral unit, and more particularly, to a digital multifunction peripheral that has a fingerprint reader capability using a scan function provided for the digital multifunction peripheral.
2. Description of the Related Art
Japanese Official Gazette, JP-A-2003-123060 discloses an invention that relates to a method and an apparatus for biometrically identifying the user of an MFP (Multifunction Peripheral). The MFP proposed in this invention identifies the user by reading his fingerprint using the scanner function provided for the MFP itself. Before the user uses the MFP, he places his finger on the fingerprint read position provided on the top of the scanner cover of the MFP. Upon judging that the user's finger is placed on the read position with the use of a light or pressure sensor, the MFP reads the user's fingerprint using its own scanner function. The MFP then checks the fingerprint thus read against the fingerprints of the pre-registered authorized users.
In the related art as described above, however, the carriage of the scanner has to be moved to the specified position for reading the fingerprint first, and then the fingerprint is read as the carriage moves. Hence, the user has to keep his finger placed immovably in a reliable manner while the carriage is moving since the user places his finger at the read position until the fingerprint reading ends. The user therefore needs to become aware of the instant at which the fingerprint reading starts and the instant at which the reading is completed. In the related art, however, it is difficult for the user to become aware of the instant at which the fingerprint reading starts because the fingerprint reading starts when it is triggered by the automatic detection of the finger by the sensor. Moreover, in the related art, it takes time from when the sensor detects the finger with the lamp indicating an operating state being lit ON until the carriage reaches the effective image region (that is, in the vicinity of the finger) because the fingerprint is read using the scanner function of the MFP.
This makes it more difficult for the user to become aware of the instant at which the fingerprint reading starts. Under these circumstances, the reading may fail because the user unintentionally moves his finger during the fingerprint reading or before or after the reading starts.
In addition, the read surfaces are not necessarily the same for the case of reading the fingerprint and for the case of reading normal documents. Hence, there is a problem that when the focus of the optical system in the scanner is adjusted to one of the read surfaces, the correct focus is not achieved on the other read surface.